This invention relates generally to refrigerators and, more particularly, to methods and systems for detecting refrigerator door openings.
Known refrigerator typically include a defrost system and one or more cooling system fans for moving air inside the refrigerator. The efficiency of the defrost system and the cooling system often are affected by and depend on the frequency and duration of opening of freezer and/or fresh food compartment doors. For example, a defrost may need to be executed as often when the doors are only infrequently opened, and operation of fans when the doors are open, thereby blowing cold air into the room is undesirable. Therefore, it is desirable for a refrigerator control system to detect the opening and closing of refrigerator and/or freezer compartment doors so that the refrigerator systems may be operated optimally and energy efficiently.
One known method of detecting refrigerator door openings employs low-voltage magnetic (Hall effect) switches in positions redundant to door light switches. Magnetic switches, however, are expensive, and entail additional product assembly. Another known method of detecting refrigerator door openings employs detection circuits on each respective door interior light circuit, thus requiring a separate detection circuit for each door. Separate detection circuits also increase costs.